Blog Archives

Large-scale replication projects of the last years (e.g., ManyLabs I, II, and III, Reproducibility Project: Psychology) showed that the “replication crisis” in psychology is more than just hot air: According to recent estimates, ~60% of cur...

There are at least three traditions in statistics which work with a kind of likelihood ratios (LRs): the “Bayes factor camp”, the “AIC camp”, and the “likehood camp”. In my experience, unfortunately most people do no...

[This is a guest post by Eric-Jan Wagenmakers and Quentin Gronau introducing the RGraphCompendium. Click here to see the full compendium!] Every data analyst knows that a good graph is worth a thousand words, and perhaps a hundred tables. But how shoul...

A Bayes factor (BF) is a statistical index that quantifies the evidence for a hypothesis, compared to an alternative hypothesis (for introductions to Bayes factors, see here, here or here). Although the BF is a continuous measure of evidence, humans lo...

[Update Oct 2014: Due to some changes to the Bayes factor calculator webpage, and as I understand BFs much better now, this post has been updated …] I started to familiarize myself with Bayesian statistics. In this post I’ll show some insig...

[mathjax] I want to present a re-analysis of the raw data from two studies that investigated whether physical cleanliness reduces the severity of moral judgments – from the original study (n = 40; Schnall, Benton, & Harvey, 2008), and from a ...

In a recent post on the DataColada blog, Uri Simonsohn wrote about “We cannot afford to study effect size in the lab“. The central message is: If we want accurate effect size (ES) estimates, we need large sample sizes (he suggests four-digi...

Update June 2013: A systematic analysis of the topic has been published:Schönbrodt, F. D., & Perugini, M. (2013). At what sample size do correlations stabilize? Journal of Research in Personality, 47, 609-612. doi:10.1016/j.jrp.2013.05.009 Check ...

“If you torture the data long enough, it will confess.” This aphorism, attributed to Ronald Coase, sometimes has been used in a disrespective manner, as if was wrong to do creative data analysis. This view obviously is misleading. In contra...